Tag Archives: Trihalomethanes

Comments Off on West Limerick Drinking Water Supplies May Be Affected By THMs

The use of chlorine to purify drinking water is common in rural water schemes throughout Ireland and is essential to ensure safe drinking water. However, if organic matter is present it can react with the chlorine to form trihalomethanes or (THMs). This is often the case in Ireland, as most of our drinking water comes from surface-water sources, such as rivers, lakes and streams, that often have high levels of vegetation or organic matter.

In a report published by the Irish Times, it shows that some studies have suggested a link between cancer and long-term exposure (over years) to THMs, and also that THMs can have an effect on reproduction. According to the Irish Time article, there is some evidence that THMs cause cancer in animals. As a result, they are classified as “possibly carcinogenic” to humans. In Ireland, THM’s have been known to occur in some counties where the surface water is sourced from areas close to boggy or peat soils. This means that some areas of West Limerick such as Athea, Ashford, Tournafulla could be affected. The vegetation and organic matter in these water supplies reacts with chlorine (which is used to purify the water) to form Trihalomethanes.

What are THMs? Trihalomethanes (THM’s) occur when water containing natural organic matter or vegetation is treated with chlorine to purify it. The result is a disinfection by-product known as THMs. At elevated levels, THMs have been associated with negative health effects such as cancer and adverse reproductive outcomes.

For anyone living in the affected areas or who anyone worried about THMs and other chemical contaminants in their drinking water, a quality under-sink water filter or water filtration system will purify the water for drinking and provide long term protection and peace of mind. Read More…